| 摘要 |
PURPOSE:To provide a mold for injection molding as well as the manufacturing method of a bolt, which are capable of supplying various kinds of bolts, having the same outer diameter but different length of the shaft thereof, and especially ceramics bolts efficiently and inexpensively. CONSTITUTION:In a mold for injection molding, in which molten compound is poured into a cavity, a liner is constituted of a fixed liner unit 2, molding the screw thread part of a bolt, and a plurality of sectional liners 3-7 for molding the head 16 and the shaft 12 of the bolt while the injection molding mold is provided with a structure, in which the sectional liners for molding the shaft part are pinched between the liner 3 for the head part and the fixed liner unit 2 so as to obtain the necessary length of the shaft. |
